title: 3D MPRAGE improves classification of cortical lesions in multiple sclerosis.
abstract: BACKGROUND
  Gray matter lesions are known to be common in multiple sclerosis (MS) and are suspected to play an important role in disease progression and clinical disability. A combination of magnetic resonance imaging (MRI) techniques, double-inversion recovery (DIR), and phase-sensitive inversion recovery (PSIR), has been used for detection and classification of cortical lesions. This study shows that high-resolution three-dimensional (3D) magnetization-prepared rapid acquisition with gradient echo (MPRAGE) improves the classification of cortical lesions by allowing more accurate anatomic localization of lesion morphology.
  
  
  METHODS
  11 patients with MS with previously identified cortical lesions were scanned using DIR, PSIR, and 3D MPRAGE. Lesions were identified on DIR and PSIR and classified as purely intracortical or mixed. MPRAGE images were then examined, and lesions were re-classified based on the new information.
  
  
  RESULTS
  The high signal-to-noise ratio, fine anatomic detail, and clear gray-white matter tissue contrast seen in the MPRAGE images provided superior delineation of lesion borders and surrounding gray-white matter junction, improving classification accuracy. 119 lesions were identified as either intracortical or mixed on DIR/PSIR. In 89 cases, MPRAGE confirmed the classification by DIR/PSIR. In 30 cases, MPRAGE overturned the original classification.
  
  
  CONCLUSIONS
  Improved classification of cortical lesions was realized by inclusion of high-spatial resolution 3D MPRAGE. This sequence provides unique detail on lesion morphology that is necessary for accurate classification.
authors.affiliation: University of Texas, Medical School at Houston, Department of Neurology, Multiple Sclerosis Research Group, 6431 Fannin Street, MSB 7.044 Houston, Texas 77030, USA. flavia.m.nelson@uth.tmc.edu
authors.forename: F
authors.initials: F
authors.lastname: Nelson
authors.forename: A
authors.initials: A
authors.lastname: Poonawalla
authors.forename: P
authors.initials: P
authors.lastname: Hou
authors.forename: J S
authors.initials: JS
authors.lastname: Wolinsky
authors.forename: P A
authors.initials: PA
authors.lastname: Narayana
mesh_terms: D000328:Adult; D000368:Aged; D001921:Brain / Q000473:pathology; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging / Q000379:methods* / Q000592:standards; D008297:Male; D008875:Middle Aged; D020528:Multiple Sclerosis, Chronic Progressive / Q000145:classification* / Q000473:pathology*; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000145:classification* / Q000473:pathology*; D010865:Pilot Projects; D015203:Reproducibility of Results